Heart disease is a leading cause of death among cats and dogs. Vertebral heart scale (VHS) is one tool to quantify radiographic cardiac enlargement and to predict the occurrence of congestive heart failure. The aim of this study was to evaluate the performance of artificial intelligence (AI) performing VHS measurements when compared with two board-certified specialists. Ground truth consisted of the average of constituent VHS measurements performed by board-certified specialists. Thirty canine and 30 feline thoracic lateral radiographs were evaluated by each operator, using two different methods for determination of the cardiac short axis on dogs' radiographs: the original approach published by Buchanan and the modified approach proposed by the EPIC trial authors, and only Buchanan's method for cats' radiographs. Overall, the VHS calculated by the AI, radiologist, and cardiologist had a high degree of agreement in both canine and feline patients (intraclass correlation coefficient (ICC) = 0.998). In canine patients, when comparing methods used to calculate VHS by specialists, there was also a high degree of agreement (ICC = 0.999). When evaluating specifically the results of the AI VHS vs. the two specialists' readings, the agreement was excellent for both canine (ICC = 0.998) and feline radiographs (ICC = 0.998). Performance of AI trained to locate VHS reference points agreed with manual calculation by specialists in both cats and dogs. Such a computer-aided technique might be an important asset for veterinarians in general practice to limit interobserver variability and obtain more comparable VHS reading over time.

Argon inhalation attenuates multiorgan failure (MOF) after experimental ischemic injury. We hypothesized that this protection could involve decreased High Mobility Group Box 1 (HMGB1) systemic release. We investigated this issue in an animal model of MOF induced by aortic cross-clamping. Anesthetized rabbits were submitted to supra-coeliac aortic cross-clamping for 30 min, followed by 300 min of reperfusion. They were randomly divided into three groups (n = 7/group). The Control group inhaled nitrogen (70%) and oxygen (30%). The Argon group was exposed to a mixture of argon (70%) and oxygen (30%). The last group inhaled nitrogen/oxygen (70/30%) with an administration of the HMGB1 inhibitor glycyrrhizin (4 mg/kg i.v.) 5 min before aortic unclamping. At the end of follow-up, cardiac output was significantly higher in Argon and Glycyrrhizin vs. Control (60 ± 4 and 49 ± 4 vs. 33 ± 8 mL/kg/min, respectively). Metabolic acidosis was attenuated in Argon and Glycyrrhizin vs. Control, along with reduced amount of norepinephrine to reverse arterial hypotension. This was associated with reduced interleukin-6 and HMGB1 plasma concentration in Argon and Glycyrrhizin vs. Control. End-organ damages were also attenuated in the liver and kidney in Argon and Glycyrrhizin vs. Control, respectively. Argon inhalation reduced HMGB1 blood level after experimental aortic cross-clamping and provided similar benefits to direct HMGB1 inhibition.